NASA to report “potential” liquid water on Enceladus
Drudge report has a copy of the press release scheduled to be released today at 2pm.
NASA’s Cassini spacecraft may have found evidence of liquid water reservoirs that erupt in Yellowstone-like geysers on Saturn’s moon Enceladus. The rare occurrence of liquid water so near the surface raises many new questions about the mysterious moon.
[...]
“Other moons in the solar system have liquid-water oceans covered by kilometers of icy crust,” said Andrew Ingersoll, imaging team member and atmospheric scientist at the California Institute of Technology, Pasadena, Calif. “What’s different here is that pockets of liquid water may be no more than tens of meters below the surface.”
Liquid water, of course, is one of the things that most scientists consider necessary for life to potentially develop, which makes this announcement so exciting. While there may be liquid water, my money is on there not being life on Encedalus. Time will tell.
[tags]Enceladus, E.T., alien life, Saturn, NASA[/tags]
Jupiter growing a second red spot
Jupiter seems to be growing a second red spot as you can see in the image above. The official name is Oval BA, but Red Jr seems to be a better choice. Red Jr first appeared in the year 2000 when three smaller spots collided and merged. It is the same color as the original red spot which is at least 300 years old and is twice as wide as the Earth. Red Jr. wasn’t always red: (more…)
Tackling malaria using distributed computing
Malaria caused by Plasmodium falciparum is one of the leading causes of death in the third world, especially among children. Becoming immune to all of the variations of Plasmodium malaria can take upwards of five years. The reason for this is because of the cloaking capabilities the parasite has evolved over the years. A process called epigenetic silencing allows the Plasmodium to express only one antigenic protein at a time. As there are about 60 genes that can be turned on and off, this means the body must learn to recognize 60 different forms of the same organism.
A distributed computing project out of France aims to tackle drug-discovery for Plasmodium-mediated malaria. Using software developed by the Fraunhofer Institute — the same people that developed the MP3 codec — the project narrows down the list of possible drug candidates to a select few which will be further analyzed by supercomputer.
The project, called Wide In Silico Docking on Malaria (WISDOM) to model 3D structures of proteins from Plasmodium to ligands: the chemical compounds that bind to protein receptors. The massive parallelism was achieved by assigning one ligand to one protein to each node on the grid. Computing the probability of a match can take a few seconds to a few minutes.
The project joins myriad other distributed computing projects in the life sciences, many of which are specifically drug-discovery efforts for diseases ranging from cancer to AIDS to anthrax and even Ebola.
[tags]WISDOM, distributed computing, grid computing, malaria, plasmodium falciparum[/tags]
Hydrogen tablets developed
Scientists at the University of Denmark have made a leap forward by creating a hydrogen tablet that stores hydrogen in an inexpensive and safe material. Because hydrogen gas is flammable and is extremely light, scientists have long had issues storing it safely and effectively. Storing enough hydrogen gas at normal pressure to drive a car 600Km would require a fuel tank the size of nine cars. (What kind of car you’d be driving, how fast you’d be traveling, and what size car would be used as a storage device is left as an exercise to the reader.)
The new method is quite different.
The hydrogen tablet is safe and inexpensive. In this respect it is different from most other hydrogen storage technologies. You can literally carry the material in your pocket without any kind of safety precaution. The reason is that the tablet consists solely of ammonia absorbed efficiently in sea-salt. Ammonia is produced by a combination of hydrogen with nitrogen from the surrounding air, and the DTU-tablet therefore contains large amounts of hydrogen. Within the tablet, hydrogen is stored as long as desired, and when hydrogen is needed, ammonia is released through a catalyst that decomposes it back to free hydrogen. When the tablet is empty, you merely give it a “shot” of ammonia and it is ready for use again.
I can see it now: we’ll all go to our gas stations and fill up on ammonia — which is dangerous — and drive around in our quiet H-powered cars. Cars powered by hydrogen do not emit carbon dioxide (or carbon monoxide, for that matter), and the hydrogen can be produced by renewable energy sources, such as wind power, completely cutting fossil fuels out of the picture.
I’d like more details on the conversion process from ammonia to free hydrogen. Jan-Willem points out that the storage of hydrogen is largely the last/greatest barrier to widespread hydrogen fuel cell adoption. (Besides inertia.)
Bullets: armor-piercing shells, gluten, and transferred toxins
It’s time for another bullet roundup. Lots of cool stuff, but without enough substance to really create a real post about them. Nonetheless, they’re worth posting about.
- New shells that use a chemical reaction to burn through armor plating are on the horizon. Instead of using depleted uranium shells which are toxic to the environment, the new technique uses to chemicals, that, when mashed together, create tremendous heat almost instantly, burning through armor. I wonder what this hopes to accomplish, save burning a hole in something. Will there be some sort of anti-personnel round underneath, or will the reaction simply burn everyone to death instead?
- New advances when it comes to isolating the toxins that cause wheat gluten intolerance. One person out of 200 in the West is affected by gluten intolerance, which severely limits their diet. A person who is wheat gluten intolerant cannot eat pasta, cereal, bread, or many of the other staples that most people enjoy. By isolating the two aggravating types, this raises hopes that wheat products without these two toxins can be developed.
- Household toxins can be transferred across the placenta. This isn’t especially surprising, since most foreign substances cross the placenta but it’s worth mentioning in the light of Hurricane Katrina. Jonathan has a good writeup in this week’s Science.Ars that explains why toxins in battered New Orleans are as big a health issue as disease proliferation through dirty water. In the case of a fetus, these toxins, including plasticizers, can cause significant damage to a developing baby.
Two girls for every boy
In the Aamjiwnaang community near Ontario, Canada, there has been a sharp fall off in birth rates of male children. Between 1999 and 2003, 86 girls were born compared to just 46 males. Assuming gender is random, it is within the realm of possibility that this could happen assuming one birth is independent from the next, but it’s extremely unlikely. Birth rates of males began dropping around 1993, and the ratio has become more skewed since then, almost certainly pointing to some external cause.
The probable cause is high levels of hexachlorobenzene (HCB) — which can disrupt hormone balances — and phthalates. Phthalates are plasticizers: they make hard plastic malleable, such as turning PVC into a flexible plastic. They’re also found in things like nail polish. Those living in the Aamjiwnaang community haven’t been tested for chemicals for some reason, but the chemicals at the top of the list of possible culprits.
Most guys might love to be born into a community where the ratio of men to women is skewed so badly, but many of the males born have slight birth defects, as male fetuses exposed to phthalates in the womb have smaller penises than males who have not.
While not conclusive until chemical testing has been done — despite what the New Scientist article says — this is the first research being done that might show direct evidence of chemicals feminizing fetuses in the womb.
“Me-too” drugs fuel rising costs
This isn’t surprising at all, as someone who works in the field, but these so-called “me-too” drugs which are reportedly better than their forebears is driving costs.
A “me-too” drug is a drug that has its origins in another drug. Probably the most famous example of this is Prilosec (”The Purple Pill”) and Nexium (”Today’s Purple Pill”). Prilosec’s active ingredient is omeprazole. Nexium’s active ingredient is called esomeprazole.
What’s the difference? Well, Nexium is the left-handed version of omeprazole. In chemistry, S stands for sinister, which means the molecular conformation has a left-handed orientation. (D would be right handed.) So this S-omeprazole is one half of the mixture that comprises it’s predecessor. By specifically picking only the S conformation, the drug is made more potent. This sounds great, but its efficacy is only marginally better than Prilosec — which has a generic version, and costs about a third less than Nexium.
Is this slight increase in efficacy worth 1/3 more? Well, AstraZeneca’s own research suggests that they are not. Nexium was created because AZ’s patent on Prilosec was finally running out, and they wanted to continue to making money from one of their flagship drugs so they released a new version that costs more and performed only partially better. This is the classic definition of a “me-too” drug. Often the research is sort of doctored to make the new drug seem much better than the old. In the case of Nexium, the literature put out by AstraZeneca compared 20mg of Prilosec to 40mg of Nexium. Of course Nexium performed better.
I spoke with an acquaintence who happened to be a drug rep for AstraZeneca, and one of his drugs had been Nexium. He told me that AstraZeneca had compared 40mg of Nexium to Prilosec, and the difference was so negligible that they simply suppressed it, and opted to publish the lobsided 20mg-40mg comparison. He also admitted that Nexium was only released because the patent on Prilosec was expiring.
Some other “me-too” drugs come readily to mind:
- Claritin (loratidine) and Clarinex (desloratidine)
- Celexa (citalopram) and Lexapro (escitalopram)
- Nexium (esomeprazole) and Prilosec (omeprazole)
Generally, these me-too drugs are released as a means to beat patent expiry, as I explained above. In the case of Claritin, not only was the patent expiring, but it went over-the-counter. Almost no insurance companies will pay for Clarinex because it’s so similar and doesn’t demonstrably work better.
Some of these “me-too” drugs are better in most cases without doctoring research findings. Lexapro, for instance, is more potent because only the S enantiomer has any effect in the body, so Forrest opted to remove the D component entirely — citalopram vs. escitalopram. The result is a drug with a lesser side effect profile, and a greater success rate. Nonetheless, it is also a “me-too” drug, and is more expensive than Celexa (for which a generic is now available).
Given everything I’ve said above, it should come as no surprise that these more expensive “me-too” drugs cost the medical industry money. Coupled with an effective marketing campaign — drug reps and direct-to-consumer advertising — patients clamor for the newer drugs, and doctors write for them. If I were a big pharmaceutical company, I’d probably do exactly what AstraZeneca and others have done, simply because it’s good for the bottom line, despite the fact that it contributes to the rising cost of health care in the United States.